function isvalidpostcode(checkpostcode) {
//	alert('isvalidpostcode') ;
	var r, myre, pcformatmsg, pcin, myrer, pcinr ;
	var retval = '!No Result found for postcode.' ;
	pcformatmsg = 'Please ensure that you have entered your full UK postcode.\n' +
				'Your postcode should be in the format:\n' +
				'(1 or 2 letters)(a number)(a number or a letter or nothing)(a number)(2 letters)\n' +
				'For example: N7 8QP, SW11 4HE or W1A 1AB';
	pcformatmsg = 'Please put in your full postcode.\n' +
				'If you are unsure of your postcode then use the map option below the postcode box.' ;
	myre = /^[A-Za-z]{1,2}[0-9]{1}[A-Za-z0-9]{0,1}[0-9]{1}[A-Za-z]{2}$/g ;
	myrer = /[\s]/g ;

	pcin = checkpostcode ;
	pcinr = pcin.replace(myrer, '') ;
	if (pcinr==null) {
		pcinr = pcin ;
	}
	else {
		retval = pcinr ;
	}

	if(myre.test(pcinr) != true) {
		retval = '!' + pcformatmsg ;
	}
	else {
		retval = pcinr ;
	}

	return retval ;
}